Order–disorder and structural phase transitions in solid‐state materials by Raman scattering analysis

INS, DFT and temperature dependent IR investigations of dynamical properties of low temperature phase of choline chloride

“…It is commonly known [40][41][42] that the band shape analysis provides information concerning molecular reorientational …”

Vibrational study of structural phase transitions in [(CH3)2NH2]3[Bi2Cl9] and [(CH3)2NH2]3[As2Cl9] crystals

“…Temperature evolution of the FT-IR spectra of DMACB in the frequency region assigned to asymmetric (a) and symmetric (b) n(NC 2 ) stretching vibration. (40 K) may be described by the Carabatos-Nédelec and Becker model [23] (see Fig. 5).…”

Molecular motions contributions to optical nonlinearity of N-benzyl-2-methyl-4-nitroaniline studied by temperature-dependent FT-IR, 1H NMR spectroscopy and DFT calculations

“…It will be considered further that the rotating methyl group can facilitate and involve the librations of both -NH and -CH 2 groups. The activation energy estimated from the Carabatos-Nédelec and Becker model [22] amounts to 11.09 ± 0.12 and 10.68 ± 0.08 kJ/mol for the -CH 2 and -NH stretching vibration bands (Table 1) while for the -NO 2 symmetric and antisymmetric stretching vibrations is equal to 9.07 ± 0.24 and 9.61 ± 0.18 kJ/mol, respectively. These activation energy values are typical though usually depend on compound and the type of motion and/or libration [15,[36][37][38].…”

“…The temperature dependence of C is used to determine the rotational correlation time, s c , and the activation energy, E a . To fit the experimental points alike in the MNA case [15] we used the formula (1) given by Carabatos-Nédelec and Becker which is composed of the vibrational relaxation term (linear dependence on temperature, T) and the rotational relaxation of diffuse nature (exponential) term [22]:…”